Abstract

Background

Antisense reagents can serve as efficient and versatile tools for studying gene function
by inhibiting nucleic acids in vivo. Antisense reagents have particular utility for the experimental manipulation of
the activity of microRNAs (miRNAs), which are involved in the regulation of diverse
developmental and physiological pathways in animals. Even in traditional genetic systems,
such as the nematode Caenorhabditis elegans, antisense reagents can provide experimental strategies complementary to mutational
approaches. Presently no antisense reagents are available for inhibiting miRNAs in
the nematode C. elegans.

Results

We have developed a new class of fluorescently labelled antisense reagents to inhibit
miRNAs in developing worms. These reagents were synthesized by conjugating dextran
with 2'-O-methyl oligoribonucleotide. The dextran-conjugated antisense reagents can
be conveniently introduced into the germline of adult hermaphrodites and are transmitted
to their progeny, where they efficiently and specifically inhibit a targeted miRNA
in different tissues, including the hypodermis, the vulva and the nervous system.
We show that these reagents can be used combinatorially to inhibit more than one miRNA
in the same animal.

Conclusion

This class of antisense reagents represents a new addition to the toolkit for studying
miRNA in C. elegans. Combined with numerous mutants or reporter stains available, these reagents should
provide a convenient approach to examine genetic interactions that involve miRNA,
and may facilitate studying functions of miRNAs, especially ones whose deletion strains
are difficult to generate.